Dosage-dispensing elements are employed in applications where a multitude of different raw materials in pulverous or granular form are brought together in the course of one or more mixing- and/or refining processes to produce a final product. The chemical and pharmaceutical industries can be mentioned as examples where such processes take place. While formulations in the development stage in the laboratory can be mixed from the smallest quantities, the full-scale manufacture of the final product involves industrial quantities, as this is the only way to achieve a sufficient lot size and thus an economical production. Especially in pharmaceutical chemicals, the sterility of the instruments and apparatus being used is of primary importance next to the purity of the raw materials, because only a rigorous quality management ensures that the quality standards can be maintained which have by now been established within the context of certification processes in almost all segments of industry. Under this aspect, it is of special importance that the equipment involved is immediately after use subjected to cleaning procedures, some of which are extremely costly, before the equipment can be put back into operation after it has passed a diversity of hygiene tests and function checks. Eminently critical in the production of chemicals, especially in the manufacture of pharmaceuticals, is the transfer of raw materials and intermediate products into the intermediate storage containers and/or mixing containers, and the transfer into shipping- or storage containers at the end of the production process.
In order to be able to dispense defined quantities of formulation components as accurately as possible even if the quantities are large, one uses dosage-dispensing elements with variable outlet openings. These can be arranged not only between the containers but also inside of hose conduits to provide the ability of manually or automatically controlling the product flow dependent on the precision and speed required in the dosage-dispensing process.
The problem with using this kind of a dosage-dispensing element is that during the filling- or dispensing process at least the inside of the element is in permanent contact with the product being dispensed. This has the consequence that one either has to use a special dosage-dispensing element for each substance that is to be dispensed in order to extend the usage intervals, or else to perform the cleaning and checking of the dosage-dispensing element after each dispensing process, especially in view of the aforementioned quality standards, in order to prevent cross contamination.
Of additional concern is the fact that after the completion of the dispensing process or after removing the filled container, the user of the filling apparatus can come into contact with the dispensed product for a certain time interval. This is the case for example if there are still product residues present in the dosage-dispensing element and/or if a pulverous product with a tendency for spreading dust is being dispensed. It cannot be excluded in such a case that the user may become contaminated and that his/her health may be endangered by contact with the user's skin, mucous membranes or respiratory tract.
In order to eliminate the last-mentioned aspect and to reduce the associated risks as much as possible, an emptying device for bags is proposed in EP 0 835 829, with an inner bag and an outer bag (so-called bulk bags), wherein the device includes a holder device for bulk bags and a dual-tube device with an inner tube and an outer tube is arranged in centered alignment below the holder device. In the inner tube, this emptying device preferably has an up-and-down movable gripper device which serves to grip the bottom of the inner bag and which can be pulled from an up-position to a down-position by means of a pulling device that is operable from the outside.
A device to empty and fill flexible containers for pourable materials without causing contamination is described in WO 2005/056443. This device uses a film hose as connecting member between a container that is to be emptied and a connecting hose or an inlet opening. After the filling/emptying process, the film hose is tied off and separated together with the flexible container and/or the filled container, and the contaminated film hose is disposed of.
In DE 198 06 932 A1, a device is shown for the non-contaminating delivery of pourable materials from a storage container into a transport container, where at the outlet spout of the storage container, which is equipped with a closure device, an exchangeable collar is arranged which can be connected to the transport container.
A device to fill hose-shaped containers is proposed in DE 2660519 C2. The containers are stored in the area of the filling device and are pulled over the latter during the filling process. After they have been filled, the hose-shaped containers are closed and remain on the product as a food wrapper as shown in the example.
The aforementioned devices have a variety of disadvantages. Although the unintended escape of fill material is prevented as much as possible in all of the devices and, accordingly, the contamination of the surrounding space and of the attending personnel is reduced to a very large extent, the fill material in all of the proposed devices is in contact with the filling apparatus and/or the dosage-dispensing elements during the transferring- or filling process. After devices of this kind have been used in critical application areas it will therefore be necessary to clean or decontaminate the entire filling- or dosage-dispensing device. A suitable cleaning process takes much time and expense and involves a series of checks before the filling- or dosage-dispensing device can be put back into operation.
It is therefore the object of the present invention to provide dosage-dispensing elements which can be used without causing contamination and can be cleaned quickly, easily and economically.